Bulletin of Botanical Research

Collation and Exploration of Centennial Plant Specimen Information in Heilongjiang Provincial Museum

Haoji WANG, Hongchao BAI, Weijing GAO, Ximing ZHAO, Yuning LIU, Yuxiao DU, Xiujuan YANG, Baojiang ZHENG

2024, 44(3): 321-329. doi:10.7525/j.issn.1673-5102.2024.03.001

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In order to understand the history of plant specimen collection in the Middle East Railway area in the 20th Century， the collection history of plant specimens from Heilongjiang Provincial Museum was systematically sorted out through the digital informationization， and a large number of relevant documents were consulted and analyzed. A total of 3 659 numbered plant specimens collected along the Middle Eastern Railway were sorted out， including 1 500 species of plants in 137 families and 578 genera， 20 wild plants under national key protection. The main collectors include T. P. Gordeev， V. N. Jernakov， V. S. Pokrvsky， I. V. Kozlov from the former Soviet Union， and Liu De from China. The collection covered five provinces， most of which were collected from Heilongjiang Province and the eastern part of the Inner Mongolia Autonomous Region， and a few were collected from Liaoning， Jilin and Hebei Province， 77.23% of the specimens were collected before 1949. Most families collected were Asteraceae， Poaceae and Rosaceae， accounted for 28.50% of the total plant specimens， and Artemisia， Salix， and Carex， accounted for 7.29% of the total plant specimens. Based the information， the current collated information might help to fill in the gaps in the history of plant collection in northeast China and provided reliable reference data for future research on plant classification， flora and phytogeography in northeast China and Inner Mongolia.

Study on the Seed Flora of Qinghai Lake Basin, China

Yuhu WU, Zhe PANG, Huilan SHI

2024, 44(3): 330-340. doi:10.7525/j.issn.1673-5102.2024.03.002

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Located in eastern Qinghai， China， the Qinghai Lake basin extends between latitudes 36°15′-38°15′N and longitudes 97°50′-101°45′E at the transition zone between the Qinghai-xizang Plateau and the Loess Plateau， the elevations ranging from 3 160-4 953 m， and the total area encompasses 29 660 km²， and the climate is typified by the alpine continental variety. There were 823 species of seed plants， distributed across 231 genera of 61 families， accounting for 23.13%， 62.89% and 38.82% of the total species， families and genera found in Qinghai respectively. The results of taxonomic analysis indicated that：（1）The density of species in every square kilometer was only 2.78， which was relatively poor compared to the numerous natural areas in the Tangut region. （2）Including the endemic plant species in China， 99.00% of the fauna was temperate， which determined that the fauna was temperate in nature. （3）There were a few woody species， few ancient and primitive groups， yet the flora with perennial herbs as the core. （4）Some of the Chinese endemic species in this region were derived from their extensive relatives， which was a concrete embodiment of the young and derived nature of the region. （5）The North China Autonomous Region and the Southwest High Mountain Region both had different degrees of influence on this region. （6）There were few endemic genera， and the endemic species were primarily aquatic plants， showing the special evolution results of the unique and Hidden domain water wet environment of Qinghai Lake. （7）The core of China’s endemic species belonged to the Gansu-Xizang-Sichuan subtype， which had the highest diversity of species. Within the subregion of plants on the Qinghai-xizang Plateau， this area belonged to the Tangut region.

Micromorphological Characterization of Leaf Epidermal Trichomes of Populus in China

Yang WU, Xingyong CUI, Fulin YUAN, Zhixiang ZHANG, Ce SHANG

2024, 44(3): 341-348. doi:10.7525/j.issn.1673-5102.2024.03.003

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In order to clarify the taxonomic value and systematic significance of leaf epidermal trichomes characters， the leaf epidermal trichomes of 33 species of Populus in China were observed and analyzed by stereomicroscope and scanning electron microscope. The results showed that Trichomes of Populus were overall non-glandular， simple， basally fixed； and all species except P. euphratica were covered with trichome in leaf epidermis， but the distribution， appearance， and length of the trichomes varied to different degrees among species. The shape of the trichomes（cylindrical to striped）， the degree of curvature（erect to curled）， the orientation relative to the surface of the leaf epidermis（ambulatory or not）， and the length of the trichomes were of taxonomic significance. Combined with the evolutionary framework provided by molecular phylogenetic studies， this study concluded that leaf epidermal indumentum characters of Populus were difficult to distinguish at the subgeneric level， the leaf trichomes within subg. Tacamahaca were similar and stable， but the length of leaf trichomes on different branches was different， however， many species could be distinguished between subg. Turanga and subg. Populus. Leaf trichomes characters could be divided into the following types after the integration of characters： glabrous， felted， sericeous， pubescent and villous.

Germplasm Innovation and Characteristic Analysis of Transgenic PsnNAC007Populus simonii×P. nigra with High Drought Tolerance

Xiaoqian WU, Xu HE, Jinghui GAO, Shuang LI

2024, 44(3): 349-360. doi:10.7525/j.issn.1673-5102.2024.03.004

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Populus simonii×P. nigra is a fast-growing and cold-tolerant tree species with elite wood properties in northeast China. In order to produce a new forest germplasm with more widely planting and improved drought tolerance， this study successfully generated transgenic P. simonii×P. nigra using PsnNAC007， a key drought response transcription factor gene. Growth characteristics， drought tolerant ability， net photosynthetic rate（P_n）， transpiration rate（T_r）， stomatal conductance（G_s）， water conductance， cell morphology and wood components of overexpressed PsnNAC007 transgenic plants were analyzed respectively. The results showed that there was no significant difference in growth between transgenic and wild-type plants， but drought survival rate was increased by 26.15%. Under drought condition， transgenic plants exhibited reduced Cleaf and T_r， improved water use efficiency， and lower water conductance loss. Anatomical analysis showed that the overexpression of PsnNAC007 led to more and smaller stem xylem vessels， which were conducive to the continuous and efficient water transport in plants under drought conditions. Based on wood components analysis， lignin deposition in stems of transgenic plants was increased significantly， and monosaccharides that constituted cellulose and hemicellulose showed no significant change.

Establishment of Genetic Transformation System for ‘Populus leucopyramidalis 1’ and Transformation of Insect Resistance Gene

Dongyue WANG, Ruyue WANG, Maotong SUN, Cuishuang LIU, Jihong LI

2024, 44(3): 361-369. doi:10.7525/j.issn.1673-5102.2024.03.005

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‘Populus leucopyramidalis 1’ is an excellent poplar clone with narrow crown and saline-alkali tolerance. Due to the lack of its genetic transformation system， genetic improvement could not be achieved through genetic engineering methods. In this study， an Agrobacterium mediated genetic transformation system of ‘P. leucopyramidalis 1’ was established and the high genetic transformation efficiency was achieved. Firstly， the tissue culture seedlings were subcultured at different time periods（35， 45， 55， 65 d）， and three types of tissues（leaves， petioles， and stem segments） were taken to compare the differentiation ability， and it was determined that the leaves sub-cultured after 45 d had the strongest differentiation ability， with a proliferation ratio of 8.77. Then， leaves sub-cultured after 45 d were used for genetic transformation， and the effects of different infection conditions on the transformation rate were examined. Orthogonal experiments were established with three gradients of bacterial concentration， infection time， and co-culture time to screen the best levels of these three factors， and the transgenic strains were identified through PCR detection and GUS staining. The results showed that the optimal combination for the genetic transformation system of ‘P. leucopyramidalis 1’ was bacterial concentration OD₆₀₀=0.4， infection-time 15 min， and co-cultivation time 2 d could reach the highest transformation rate 54.23%. Finally， the ‘P. leucopyramidalis 1’ transgenic strain of BtCry3Aa insect resistant gene using this genetic transformation system was obtained， and the results proved that this system could be an effective method for genetic improvement of ‘P. leucopyramidalis 1’.

Breeding System and Hybridization Affinity of Rhododendron irroratum

Wenyan XIONG, Yawen WU, Tian BAI, Weijia XIE, Yan DONG, Jingli ZHANG

2024, 44(3): 370-379. doi:10.7525/j.issn.1673-5102.2024.03.006

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To protect germplasm resources and provide technical support for native garden species， the breeding system and hybrid affinity of wild Rhododendron irroratum were studied. The experiments included flowering biological characteristics， the characteristics of breeding system and the cross pollination with fine horticultural varieties of Rhododendron. The process of pollen germination and pollen tube growth were observed by fluorescence microscope， and the fruiting and seed setting were calculated. The results showed that （1） the flowering time of R. irroratum dewdrop was from late April to late May， and pollen viability and stigma receptivity decreased gradually with the extension of flowering time. （2）Hybridization index（OCI） was 3， P/O value was 343.47. （3）The main pollinator was Apis cerana. The breeding system was facultative outbred， self-compatible， requiring pollinators. （4）No apomixis was found in artificial pollination， which could automatically self-pollinate. The fruit setting rates of different strains cross-pollination， strains cross-pollination and self-pollination were 46.96%， 45.03% and 37.16% respectively. The average fruit setting rate of artificial pollination was basically consistent with that of natural pollination. （5）The hybrid incompatibility was observed in the parent for artificial cross pollination. Fluorescence microscopy revealed callose embolism in the pollen tube of the mother， which prevented the tube from extending to the ovary. Through observation， it is found that the difficulty of cross compatibility lies in pollen tube growth process.

Characteristics of Fine Root Morphology and Biomass Vertical Distribution from Different Provenances and Families of Picea koraiensis

Yanru GAO, Junhui WANG, Wenjun MA, Fude WANG, Sanping AN, Jiacun GU

2024, 44(3): 380-388. doi:10.7525/j.issn.1673-5102.2024.03.007

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In order to reveal the characteristics of fine root（diameter ≤2 mm） morphology and vertical distribution of biomass from different provenances and families of 24-year-old Picea koraiensis， the soil core method was used to determine fine root morphology and biomass at different soil layers（surface layer： 0<h≤ 10 cm， subsurface layer： 10 cm<h≤20 cm， bottom layer： 20 cm<h≤30 cm） in 30 families from four provenances（Muling， Linkou， Jinshantun， and Wuyiling from low to high latitude） in Qingshan Forest Farm， Linkou County， Heilongjiang Province， China. The results showed that there were significant differences in all fine root morphological traits among different provenances， and specific root length and root tissue density exhibited significant differences among families within provenance. At the provenance level， the average root diameter of Wuyiling provenance was the thickest at all soil layers， whereas specific root length and root tissue density of Linkou provenance were the largest. At the family level， in 0<h≤10 cm soil layer， root diameter of W035 was the thickest， that of CK-2 was the thinnest， specific root length of CK-2 was the longest， that of W043 was the shortest， root tissue density of J082 was the highest， that of M515 was the lowest. Root tissue density and specific root length of different provenances and families of P. koraiensis decreased with the increase of soil layer， while root diameter increased. The total fine root biomass（all three soil layers） across the four provenances was 33.56 g·m^-2 on average， with the maximum occurring in Linkou provenance （39.04 g·m^-2） and the minimum in Jinshantun provenance（32.52 g·m^-2）， showing inconsecutive geographical distribution. Fine root biomass decreased with soil layer increasing， and root biomass at the surface soil layer accounted for 77% of the total biomass on average. In comparison， the low-latitude provenance of Muling tended to distribute greater fine root biomass at the subsurface and bottom soil layers， while the high-latitude provenances of Wuyiling and Jinshantun had higher fine root biomass at the surface soil layer， indicating that P. koraiensis originated from cold site tended to allocate more fine roots at the fertile surface soil.

Morphological Adaptation to Alpine Environment of a Chinese Endemic Species, Cynanchum forrestii

Shuanglong TANG, Shixin CHEN, Yu WANG, Danwei MA, Shihui YANG, Shenming NIE, Zhaxizeli, Zhengyou TIAN

2024, 44(3): 389-399. doi:10.7525/j.issn.1673-5102.2024.03.008

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Alpine meadows exhibited environmental characteristics such as intense radiation， low air pressure， strong winds and sudden changes in diurnal temperature， which were unfavorable for plant growth. In order to explore the ecological adaptability of Cynanchum forrestii， an endemic species of China to the alpine meadow environment（altitudes of 3 100-3 500 m） in Jiulong County， southwest Sichuan Province， the anatomical features of various organs of C. forrestii were examined by optical microscopy and scanning electron microscopy， and the pollen and seed viability were analyzed by the TCC method. The results showed that the leaves， stems and flowers of C. forrestii were covered with epidermis composed of rich single-row cells； the cuticle of leaf and stems epidermis was thick； the stomata were large and located on the lower surface of the leaves， palisade tissue and sponge tissue were developed； the stem epidermal cells were small and the cell wall was thick， and the cortex was composed of seven layers of cells， which were closely arranged， there were rich substances stored in the stem cells， and the vascular columns accounted for a large proportion of stem， the pith was developed and rich in stored substances； the root vascular tissue was well-developed， rich storage substances in cortical cells； the characteristics of high seed and pollen vitality， combined corolla， combined pistil column， the seed had seed hair， and thick and hard seed coat provide guaranteed for improving reproductive efficiency. The above results indicated that C. forrestii possessed a comprehensive array of external and internal structural characteristics， which enabled adaption to high-altitude cold environments while maintaining elevated levels of radiation resistance， drought resistance， and cold tolerance， and laid a structural foundation for the successful survival and reproduction of C. forrestii in the alpine environment.

Seed Germination Characteristics of Amygdalus ledebouriana in Barluk Mountain

Yue GUAN, Wenjing SHEN, Xiaomeng SONG, Yanxin WANG, Nurgailide AKEJULIDEZI, Pengfei CHEN, Long ZHOU

2024, 44(3): 400-409. doi:10.7525/j.issn.1673-5102.2024.03.009

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In order to explore the obstacle factors of regeneration of Amygdalus ledebouriana in Xinjiang， and to better protect the germplasm resources and population， the seeds of A. ledebouriana in Barluk Mountain of Xinjiang were used as experimental materials， and the effects of seed water absorption characteristics， different stacking time， different concentrations of GA₃ and different substrate treatments on the dormancy and germination characteristics of A. ledebouriana seeds and the germination inhibitors in A. ledebouriana were explored respectively. The results showed that：（1）The natural dormancy of whole seeds was relieved after 80 days stratification， while the decorticated seeds could germinate without stratification， and the addition of 300 mg·L^-1 G_A3 could break the dormancy of decorticated seeds in advance and improve the germination rate. （2）The germination inhibitors in A. ledebouriana seeds mainly existed in exocarp and mesocarp. （3）The germination rate of A. ledebouriana seeds in the original habitat soil was higher than that in the nutrient soil.

Responses of Leaf and Fine Root Functional Traits of Alternanthera philoxeroides to Heterogeneous Habitats

Yandong JIANG, Zhengdong PENG, Qi XU, Wanyi GAN, Liujing HUANG

2024, 44(3): 410-419. doi:10.7525/j.issn.1673-5102.2024.03.010

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Functional traits of the leaf and fine root play an important role in plant invasion. It was of great significance for understanding the biological invasion mechanism to investigate the differences and connections between the functional traits of leaf and fine root functional traits and to illustrate the responses of plants parts above and below ground to heterogeneous habitats. In this research， 20 functional traits in leaves and fine roots of Alternanthera philoxeroides in three habitats（xeric， wet， and aquatic） were measured and their differences and correlations in different habitats were analyzed by field investigation methods. The results indicated that：（1）There were significant differences（P<0.05） in plant functional traits among the three habitats， with the largest differences in leaf fresh weight（（1.12±0.14） g）， leaf area（（4.80±0.57） cm²）， and leaf volume（（1.12±0.16） cm³） in the xeric habitat， while the ratio of leaf length to width（2.95±0.22） and root tissue density （（4.14±0.52） g·cm^-3） in aquatic habitat， respectively. （2）A. philoxeroides had the highest coefficient of variation in leaf relative water content（0.603） in hydric habitat， while the lowest coefficient of variation for the ratio of leaf length to width（0.057）. In addition， it had the highest coefficient of variation for root branch number（0.453） in xeric habitat and the lowest coefficient of variation for root average diameter（0.065）. （3）Similar to leaf， fine root traits were closely related， but there were less related between root and leaf traits. （4）A. philoxeroides preferred the acquisitive strategy（high input-low return） in the xeric habitat， while it preferred the resource conservative strategy（low input-high return） in the wet and aquatic habitats.

Metabolomics Analysis of Lagerstroemia indica in Response to Salt and Alkali Stress

Hengfeng ZHANG, Yangwu HE, Huanchao ZHANG, Qingcui WEI

2024, 44(3): 420-430. doi:10.7525/j.issn.1673-5102.2024.03.011

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To explore the metabolic response mechanism of Lagerstroemia indica ‘Pink Velour’ to salt and alkali stresses， one-year-old asexual cottage seedlings were treated to salt stress（NaCl， pH=7.02） and alkali stress（NaHCO₃ and Na₂CO₃， Na⁺ mole ratio 2∶1， pH=9.52） respectively， and the leaves metabolic changes and differences of the two treatment groups and the control group（CK） were analyzed and compared by using liquid chromatography mass spectrometry（LC-MS）. The results showed that 156 and 176 different metabolites were screened in salt and alkali stress group respectively， and 23 different metabolites were screened in both groups， and the rest were unique different metabolites. KEGG enrichment analysis showed that the biosynthesis of secondary metabolites， amino acid metabolism， carbohydrate metabolism， fatty acid metabolism and plant hormone synthesis were main metabolic pathways in response to salt and alkali stress. Glycine， serine and threonine anabolism， ABC transporter protein and Vitamin B₆ anabolism were the unique metabolic pathways in salt stress groups. Biosynthesis of valine， leucine， isoleucine， arginine， proline， folic acid and ascorbic acid， and mutual transformation between pentose and glucuronic were the unique metabolic pathway in alkali stress groups. The changes of different metabolites and enriched metabolic pathways might be the main mechanism of L. indica response to the salt stress and alkali stress.

Functional Analysis of ANT Transcription Factor of Populus trichocarpa Based on CRISPR-dCas9 Transcription Activation System

Lingtong MENG, Liwei SU, Xiangxin LI, Tiansheng XIONG, Panpeng CHANG, Mengzhuo LIU, Chenguang ZHOU

2024, 44(3): 431-440. doi:10.7525/j.issn.1673-5102.2024.03.012

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The expression of gene transcription activation based on CRISPR-dCas9 might avoid phenotypic interference caused by gene ectopic expression， and made genes expressed efficiently and specifically. In this study， a novel CRISPR-Act3.0 expression system based on CRISPR-dCas9 was used to perform transcriptional activation of the vascular cambium-specific transcription factor ANT（AINTEGUMENTA） in Populus trichocarpa to create genetic materials and function analysis. First， homology analysis was conducted on the PtrANTs transcription factors of P. trichocarpa， and PtrANT-4 was selected for subsequent research. PtrANT-4 gene was cloned and its expression in various tissues was analyzed using fluorescence quantitative PCR. Secondly， three gRNAs were designed on the gene promoter of PtrANT-4， and the transcriptional activation expression vector CRISPR-dCas9/ANTprogRNAs was constructed. The expression of the vector was detected by transient protoplast transformation method. Finally， the expression vector was transformed into P. trichocarpa using Agrobacterium-mediated method， and transcription-activated genetic plants of PtrANT-4 were obtained. The results showed that there were four PtrANTs transcription factors in P. trichocarpa. PtrANT-4 was specifically expressed in vascular cambium of lateral meristem of P. trichocarpa. The transcription activation vector successfully constructed based on the CRISPR-Act3.0 expression system has the transcriptional activation effect of PtrANT-4 after transformation in xylem protoplasts of P. trichocarpa. The expression level of the PtrANT-4 gene in the genetically transformed plants was significantly increased only in the vascular cambium， suggesting that PtrANT-4 might play an important role in the development of stem vascular cambium This study lays a foundation for the functional study of PtrANT， and provides important genetic materials for the study of the mechanism of vascular cambial stem cell development.

Ploidy Level and Genome Size Variation in Sorbus sect. Sorbus(Rosaceae)

Qi QI, Wenxiang HOU, Jin QIU, Liyang GENG, Xin CHEN

2024, 44(3): 441-447. doi:10.7525/j.issn.1673-5102.2024.03.013

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In order to explore the ploidy level and genome size of Sorbus sect. Sorbus species， the nuclear DNA content from somatic cells was measured by flow cytometry and Oryza sativa subsp. japonica ‘Nipponbare’ was used as the internal control. The results showed that the genome size of 19 species ranged from 0.648 to 0.803 pg， with the diploid， triploid and tetraploid levels， including 15 diploid species with 2C values ranging from 1.335 to 1.607 pg for， and one triploid species S. himalaica with 2C values of 2.137 pg，and three tetraploid species， S. albopilosa， S. prattii and S. pseudovilmorinii， with 2C values of 2.594， 2.891 and 2.751 pg， respectively. The 2C values of 16 species and new ploidy levels of five species were reported for the first time， indicating that there were changes of ploidy heterogeneity among interspecific and intraspecific in Sorbus sect. Sorbus.

Characteristics of Apocynum venetum Community and Its Relationship to Climatic Factors

Xi ZHEN, Xuyang LIU, Wenjie LI, Feng ZHANG, Yue SU, Yao XIAO, Jie ZHANG, Tao WAN

2024, 44(3): 448-458. doi:10.7525/j.issn.1673-5102.2024.03.014

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Apocynum venetum is an important wild germplasm resource in China， and understanding the characteristics of A. venetum community and its relationship with environmental factors is of great significance for the protection and rational development and utilization of A. venetum germplasm resources. The wild A. venetum distributed in Jinta County， Minqin County， Hangjinqi， Zhaluteqi， and Baicheng City were used as materials. Based on the community composition and habitat characteristics， the biodiversity and its relationship with climate factors， and environmental factors affecting the changes in A. venetum communities were analyzed respectively. The results showed that： the species diversity of the five plots from high to low was Zhaluteqi， Minqin County， Baicheng City， Jinta County， Hangjinqi， with Zhaluteqi having the highest biodiversity（H=2.591， D=2.511， E=0.796， R₁=44.833， R₂=6.423）， and Hangjinqi had the lowest biodiversity（H=1.173， D=0.915， E=0.564， R₁=3.641， R₂=1.968）. The species diversity of A. venetum community was closely related to precipitation， temperature and evaporation， especially the Gleason and Margalef index were significantly positively correlated with precipitation in May， June and July， indicating that precipitation during the growing season was important to community species diversity.

Plant Community Characteristics and Their Relationship with Environmental Factors in Different Geomorphic Units in Arid Gravel Desert

Huadong DU, Penghui FAN, Yinli BI, Shanshan XIE, Yan LIU, Yunlong LIU

2024, 44(3): 459-469. doi:10.7525/j.issn.1673-5102.2024.03.015

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Exploring the characteristics and its driving forces of plant community in different geomorphic units in arid gravel desert areas was of great significance for the development of targeted natural plant community protection measures， and the construction of reasonable artificial restoration plant communities in different geomorphic units in arid region. In this paper， the plant community composition and diversity in four micro-geomorphic units（gravel desert Gobi， wind erosion unaka， aeolian sandy land and valley land） were analyzed， and the main ecological factors affecting plant community characteristics in different geomorphic units were explored based on the monitoring of soil and micro-meteorological factors. The results showed that：（1）Plant community in gravel desert areas was distributed in patches， with one to two layers vertical structure， and the life forms were mainly annual plants and small shrubs. About 45% shrubs were found in arid gravel desert Gobi， while about 50% species were annual plants in wind erosion unaka and aeolian sandy land. The plant community in the valley land contained all five life forms， including a few trees and vines. （2）The plant community coverage， plant density， diversity and stability were the highest in valley among four micro-geomorphic units， followed by wind erosion unaka. The plant community diversity and stability were lowest in gravel desert Gobi with the plant sparsely distributed and the aeolian sandy land with simple community structure. （3）Soil moisture content， organic matter， soluble salts and surface temperature were the main same factors affecting plant diversity， productivity and community stability in arid gravel desert areas. In addition， the soil bulk density in wind erosion unaka， the surface wind speed in arid gravel desert Gobi and aeolian sandy land were also the factors affecting plant community characteristics in different micro-geomorphic units. In summary， different vegetation restoration measures should be formulated after ecological disturbance in arid gravel desert on the basis of the main ecological factors affecting plant communities in different geomorphic units， such as reducing surface temperature in gravel desert Gobi， restoring constructive species by improving soil quality in wind erosion unaka and aeolian sandy land， and maintaining ecological water using in valley land.

Soil Enzyme Activities and Stoichiometric Characteristics of Different Plant Communities under Natural Fagus Forest in Micang Mountain Nature Reserve, Sichuan

Lijuan LUO, Qingxiao YIN, Wei SUN, Xi ZAN, Qingmao SHI, Jing ZHANG, Yamei CHEN, Xiao XU

2024, 44(3): 470-480. doi:10.7525/j.issn.1673-5102.2024.03.016

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In this study， the soil enzyme activities， stoichiometric characteristics and major environmental factors of Sarcococca ruscifolia and Fargesia spathacea communities at different depths（0<h≤10 cm， 10 cm<h≤20 cm） were examined in the natural Fagus forest in Micang Mountain Nature Reserve， Sichuan. The results showed that：（1）In different understory plant communities， the total nitrogen（TN） content in plantless community was higher than that in plant community soil. At the soil depth of 10 cm<h≤20 cm， the contents of total carbon（TC） and soil available nitrogen（SAN） were the highest in the S. ruscifolia community. （2）The soil enzyme activities （acid phosphatase（AP）， 1， 4-β-N-acetylglucosaminidase（NAG）） in the S. ruscifolia community were significantly higher than those in the no plant community and the F. spathacea community， and the activities of β-glucosidase（BG） and leucine aminopeptidase（LAP） were the highest in the F. spathacea community. The activities of polyphenol oxidase（PPO） and peroxidase （POD） in plant community were significantly higher than those in no plant community. （3）Soil enzyme activities of BG， LAP， PPO and POD were significantly positively correlated with soil pH， and soil enzyme activities（except cellobiohydrolase（CBH）） were significantly positively correlated with soil moisture content. The results of redundancy analysis（RDA） showed that soil moisture content， SAN and TC content explained 51.4%， 40.5% and 37.7% of the variation of soil enzyme activity and its stoichiometric characteristics， respectively. （4）The vector angle（VA） was greater than 45°， suggesting that soil microorganisms were more susceptible to phosphorus restriction. The results indicated that different understory plant communities could affect soil physical and chemical properties and soil enzyme activities and their stoichiometric characteristics were mainly regulated by soil moisture content， SAN and TC content.

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